<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>test cors</title>
</head>

<body>
  <h2>test cors</h2>
  <button>auto send request</button>
</body>
<script>
  fetch("http://localhost:3000/", {
    headers: {
      "Content-Type": "application/json",
    }
  }
  ).then(res => res.json())
    .then(res => {
      console.log(res);
    })
</script>

</html>